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Simon Peyton Jones pushed to branch wip/T23051 at <a href="https://gitlab.haskell.org/ghc/ghc">Glasgow Haskell Compiler / GHC</a>
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Commits:
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<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/35616f4145c0cdb83e815a967e70afd944ad4851">35616f41</a></strong>
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<span> by Simon Peyton Jones </span> <i> at 2023-03-15T18:00:07+00:00 </i>
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<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 0.875rem; color: #333238; position: relative; font-family: var(--default-mono-font, "Menlo"),"DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>Drop dead binding
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1 changed file:
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<a href="#94c96afe1bb3b771ffbcfeeca34ce43ebbe76ccb">
compiler/GHC/Tc/Utils/TcMType.hs
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Changes:
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<li id="94c96afe1bb3b771ffbcfeeca34ce43ebbe76ccb">
<a href="https://gitlab.haskell.org/ghc/ghc/-/commit/35616f4145c0cdb83e815a967e70afd944ad4851#94c96afe1bb3b771ffbcfeeca34ce43ebbe76ccb"><strong style="font-weight: bold;">compiler/GHC/Tc/Utils/TcMType.hs</strong></a>
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<td class="line_content match" style="color: rgba(31,30,36,0.24); padding: inherit;" bgcolor="#fbfafd">@@ -1444,8 +1444,8 @@ collect_cand_qtvs orig_ty is_dep cur_lvl bound dvs ty</td>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.875rem; color: #333238; position: relative; font-family: var(--default-mono-font, "Menlo"),"DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dcdcde;'> <span id="LC1444" class="line" lang="haskell">                    <span class="c1" style="color: #998; font-style: italic;">-- See Note [Use level numbers for quantification]</span></span>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.875rem; color: #333238; position: relative; font-family: var(--default-mono-font, "Menlo"),"DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dcdcde;'> <span id="LC1445" class="line" lang="haskell"></span>
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.875rem; color: #333238; position: relative; font-family: var(--default-mono-font, "Menlo"),"DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dcdcde;'> <span id="LC1446" class="line" lang="haskell">      <span class="o" style="font-weight: 600;">|</span> <span class="kr" style="font-weight: 600;">case</span> <span class="n" style="color: #333;">tcTyVarDetails</span> <span class="n" style="color: #333;">tv</span> <span class="kr" style="font-weight: 600;">of</span></span>
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<td class="new_line diff-line-num old" data-linenumber="1447" style="width: 35px; color: rgba(31,30,36,0.24); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
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<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.875rem; color: #333238; position: relative; font-family: var(--default-mono-font, "Menlo"),"DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dcdcde;'>-<span id="LC1447" class="line" lang="haskell">          <span class="kt" style="color: #458; font-weight: 600;">SkolemTv</span> <span class="kr" style="font-weight: 600;"><span class="idiff left deletion" style="background-color: #fac5cd;">_</span></span><span class="idiff deletion" style="background-color: #fac5cd;"> </span><span class="n" style="color: #333;"><span class="idiff deletion" style="background-color: #fac5cd;">lvl</span></span><span class="idiff deletion" style="background-color: #fac5cd;"> </span><span class="kr" style="font-weight: 600;"><span class="idiff right deletion" style="background-color: #fac5cd;">_</span></span> <span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">True</span>  <span class="c1" style="color: #998; font-style: italic;">-- lvl > pushTcLevel cur_lvl</span></span>
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<td class="new_line diff-line-num old" data-linenumber="1447" style="width: 35px; color: rgba(31,30,36,0.24); border-right-width: 1px; border-right-color: #fac5cd; border-right-style: solid; padding: inherit;" align="right" bgcolor="#f9d7dc">
 
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<td class="line_content old" style="padding: inherit;" bgcolor="#fbe9eb"><pre style='display: block; font-size: 0.875rem; color: #333238; position: relative; font-family: var(--default-mono-font, "Menlo"),"DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dcdcde;'>-<span id="LC1448" class="line" lang="haskell">          <span class="kr" style="font-weight: 600;">_</span>           <span class="idiff left right deletion" style="background-color: #fac5cd;">     </span><span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">False</span></span>
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<td class="old_line diff-line-num new" data-linenumber="1449" style="width: 35px; color: rgba(31,30,36,0.24); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
 
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<td class="new_line diff-line-num new" data-linenumber="1447" style="width: 35px; color: rgba(31,30,36,0.24); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.875rem; color: #333238; position: relative; font-family: var(--default-mono-font, "Menlo"),"DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dcdcde;'>+<span id="LC1447" class="line" lang="haskell">          <span class="kt" style="color: #458; font-weight: 600;">SkolemTv</span> <span class="p"><span class="idiff left right addition" style="background-color: #c7f0d2;">{}</span></span> <span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">True</span>  <span class="c1" style="color: #998; font-style: italic;">-- lvl > pushTcLevel cur_lvl</span></span>
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<td class="new_line diff-line-num new" data-linenumber="1448" style="width: 35px; color: rgba(31,30,36,0.24); border-right-width: 1px; border-right-color: #c7f0d2; border-right-style: solid; padding: inherit;" align="right" bgcolor="#ddfbe6">
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<td class="line_content new" style="padding: inherit;" bgcolor="#ecfdf0"><pre style='display: block; font-size: 0.875rem; color: #333238; position: relative; font-family: var(--default-mono-font, "Menlo"),"DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dcdcde;'>+<span id="LC1448" class="line" lang="haskell">          <span class="kr" style="font-weight: 600;">_</span>           <span class="o" style="font-weight: 600;">-></span> <span class="kt" style="color: #458; font-weight: 600;">False</span></span>
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<td class="new_line diff-line-num" data-linenumber="1449" style="width: 35px; color: rgba(31,30,36,0.24); border-right-width: 1px; border-right-color: #ececef; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fbfafd">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.875rem; color: #333238; position: relative; font-family: var(--default-mono-font, "Menlo"),"DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dcdcde;'> <span id="LC1449" class="line" lang="haskell">      <span class="o" style="font-weight: 600;">=</span> <span class="n" style="color: #333;">return</span> <span class="n" style="color: #333;">dv</span>  <span class="c1" style="color: #998; font-style: italic;">-- Skip inner skolems</span></span>
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<td class="old_line diff-line-num" data-linenumber="1450" style="width: 35px; color: rgba(31,30,36,0.24); border-right-width: 1px; border-right-color: #ececef; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fbfafd">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.875rem; color: #333238; position: relative; font-family: var(--default-mono-font, "Menlo"),"DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dcdcde;'> <span id="LC1450" class="line" lang="haskell">        <span class="c1" style="color: #998; font-style: italic;">-- This only happens for erroneous program with bad telescopes</span></span>
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<td class="old_line diff-line-num" data-linenumber="1451" style="width: 35px; color: rgba(31,30,36,0.24); border-right-width: 1px; border-right-color: #ececef; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fbfafd">
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<td class="new_line diff-line-num" data-linenumber="1451" style="width: 35px; color: rgba(31,30,36,0.24); border-right-width: 1px; border-right-color: #ececef; border-right-style: solid; padding: inherit;" align="right" bgcolor="#fbfafd">
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<td class="line_content" style="padding: inherit;"><pre style='display: block; font-size: 0.875rem; color: #333238; position: relative; font-family: var(--default-mono-font, "Menlo"),"DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: inherit; border-radius: 2px; margin: 0; padding: 0; border: inherit solid #dcdcde;'> <span id="LC1451" class="line" lang="haskell">        <span class="c1" style="color: #998; font-style: italic;">-- e.g. BadTelescope2:  forall a k (b :: k). SameKind a b</span></span>
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